/*
 * Copyright 2004-2009 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package susano.common.util;

/**
 * A utility class for {@link Long}.
 *
 * @author tanaka.akira.2006
 * @version $Id: LongUtil.java 337 2009-10-15 05:26:51Z tanaka.akira.2006 $
 *
 */
public final class LongUtil {

    private LongUtil() {
    }

    /**
     * Converts the object to {@link Long}.
     *
     * @param o
     *            the object
     * @return the converted value
     */
    public static Long toLong(Object o) {
        if (o == null) {
            return null;
        } else if (o.getClass() == Long.class) {
            return (Long) o;
        } else if (o instanceof Number) {
            return Long.valueOf(((Number) o).longValue());
        } else if (o.getClass() == String.class) {
            String s = (String) o;
            if (StringUtil.isEmpty(s)) {
                return null;
            }
            return Long.valueOf(s);
        } else if (o.getClass() == Boolean.class) {
            return ((Boolean) o).booleanValue() ? Long.valueOf(1) : Long
                .valueOf(0);
        } else {
            return Long.valueOf(o.toString());
        }
    }

    /**
     * Converts the object to primitive long.
     *
     * @param o
     *            the object
     * @return the converted value
     */
    public static long toPrimitiveLong(Object o) {
        Long l = toLong(o);
        if (l == null) {
            return 0;
        }
        return l.longValue();
    }
}
